Automated licence plate reader (ALPR) cameras have become a widespread surveillance tool in the United States, recording vehicle movements and allowing police agencies to search and potentially share the data across jurisdictions. Supporters see them as a policing aid, but the expansion has prompted privacy concerns over whether dense, long-term tracking of ordinary drivers could breach constitutional protections.

The article highlights Flock Safety as a major supplier, with the ACLU estimating that 80,000 to 100,000 Flock cameras are deployed nationwide. Recent court rulings have upheld specific ALPR systems, but have not settled whether a more extensive network capable of revealing detailed travel patterns would become constitutionally problematic. The technology can also produce errors: a Colorado woman was accused of theft after surveillance systems, including Flock cameras, wrongly linked her vehicle to the scene.